1. Ph.D. Student, Div. of Marine Engineering, Dept. of Naval Architecture and Marine Engineering, National Technical Univ. of Athens, Athens 15773, Greece.
2. Principal Researcher, Chemical Process and Energy Resources Institute (CPERI), Centre for Research and Technology Hellas, Thessaloniki 57001, Greece.
3. Professor, Div. of Marine Engineering, Dept. of Naval Architecture and Marine Engineering, National Technical Univ. of Athens, Athens 15773, Greece (corresponding author).